11.4.1 Cells And Systems

• What is the function of the testes?

  To produce sperm and testosterone
• What is the role of the scrotum?

  It holds the testes outside the body
• What is semen made of?

  Sperm mixed with fluids from glands
• What are the two functions of the penis?

  To pass urine and semen
• What is the urethra's function?

  To carry urine or semen
• What is the size of a sperm cell?

  45 micrometres
• How many sperm are produced daily after puberty?

  Over 100 million
• What is a haploid nucleus?

  A nucleus with half the DNA
• What is the function of the tail (flagellum) in sperm?

  To propel the sperm for movement
• Why do sperm cells have many mitochondria?

  To release energy for their journey
• What are acrosomes in sperm cells?

  Special enzymes to penetrate the egg
• What do the ovaries contain?

  Ova (eggs)
• When do women have ova in their bodies?

  From birth
• What is the function of the oviducts (fallopian tubes)?

  To connect ovaries and uterus
• How do ciliated cells help in the oviducts?

  They waft the ovum along
• What is peristalsis in the context of the oviducts?

  Aiding movement of the ovum
• Where does fertilization occur?

  In the oviducts
• What happens to the embryo after fertilization?

  It travels down the oviduct
• What is the uterus's structure?

  A muscular bag with a soft lining
• What happens to the uterus lining each month?

  It builds up and is lost as a period
• What is the function of the cervix?

  To keep the baby in place during pregnancy
• What occurs during sexual intercourse?

  The penis enters the vagina
• What is the size of an egg cell?

  0.2 mm
• How many eggs mature and are released each month?

  Only 1 egg
• What is the motility of egg cells?

  They have low motility
• What is the function of the large cytoplasm in egg cells?

  To store nutrients for energy
• What happens to the egg's jelly coat after fertilization?

  It changes to allow only one sperm
• Compare the adaptations of sperm and egg cells.

  Sperm cell adaptations:

  • Small size (45 micrometres)
  • Flagellum for motility
  • Many mitochondria for energy
  • Acrosomes for penetrating the egg

  
  

  Egg cell adaptations:

  • Large size (0.2 mm)
  • Low motility
  • Large cytoplasm for nutrients
  • Jelly coat that changes post-fertilization

  
• What are the main components of the male reproductive system?

  • Testes: produce sperm and testosterone
  • Sperm ducts: transport sperm
  • Glands: provide fluids for semen
  • Penis: delivers urine and semen
  • Urethra: carries urine or semen

  
• What are the main components of the female reproductive system?

  • Ovaries: contain ova (eggs)
  • Oviducts: transport ova and site of fertilization
  • Uterus: where embryo implants
  • Cervix: supports the baby during pregnancy
  • Vagina: receives the penis during intercourse